There's a lot of work in this area, in labs all over the world. Google's project Tango has funded some excellent work on this problem on a (very powerful) cellp

There's a lot of work in this area, in labs all over the world. Google's project Tango has funded some excellent work on this problem on a (very powerful) cellphone/tablet platform: https://www.youtube.com/watch?v=44vppay5UDc https://www.youtube.com/watch?v=44vppay5UDc